If you do PTAT for all channels and schedule a show for the networks in primetime, it does not record it, I believe.
You can set the show(s) to be saved and not deleted, again I believe.
I set PTAT for 1 night, 1 network to get AutoHop if I can get around to it.
But I set individual timers, with save, so that I can archive those.
I then move the day of the week around so that there is no PTAT but AutoHop will be available for a week or so.
I believe space is allocated in the 2TB for the recordings etc. leaving you 1.2TB, so that nothing is bumped by it.
-Ken